21662152 has 8 divisors (see below), whose sum is σ = 40616550. Its totient is φ = 10831072.

The previous prime is 21662129. The next prime is 21662189. The reversal of 21662152 is 25126612.

It can be written as a sum of positive squares in only one way, i.e., 20376196 + 1285956 = 4514^2 + 1134^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21662152² = 938497658542208, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1353877 + ... + 1353892.

Almost surely, 2^21662152 is an apocalyptic number.

It is an amenable number.

21662152 is a deficient number, since it is larger than the sum of its proper divisors (18954398).

21662152 is a wasteful number, since it uses less digits than its factorization.

21662152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2707775 (or 2707771 counting only the distinct ones).

The product of its digits is 1440, while the sum is 25.

The square root of 21662152 is about 4654.2617029987. The cubic root of 21662152 is about 278.7621890680.

Adding to 21662152 its reverse (25126612), we get a palindrome (46788764).

The spelling of 21662152 in words is "twenty-one million, six hundred sixty-two thousand, one hundred fifty-two".